Motor vehicle



March 28, 1944. F, C` BEST 2,345,448

MOTOR VEHICLE Filed May 7, 1938 2 Sheets-Sheet l 7 SP1/UWM March 28,1944. F. c. BEST MOTOR VEHICLE Filed May '7, 1938 2 Sheets-Shes*I 2Patented Mar. 28, 1944 MOTOR VEHICLE Frank C. Best, Detroit, Mich.,assigner to Packard Motor Car Company, Detroit, Mich.. a corporation ofMichigan Application May 7, 1938, Serial No. 206,679

y (Cl. 180-73) Claims.

opposite side, the vehicle body is thrust laterally.

For example, when one wheel meets an obstacle and rises, the axle swingsupwardly about the point of contact of the opposite wheel with the roadbed. The longitudinal vertical planes passing through the points ofconnection of the oppositely disposed springs to the axle are thusbrought closer together, and one or both of the springs must flexlaterally. 'I'hat spring which is the flatter of the two is moreresistant to lateral iiexure, and the body is displaced toward theopposite side, the opposite spring yielding laterally to permit suchmovement. 'I'he lateral impact thus appliedto the body is usually severeowing to the edgewise stiffness of the conventional leaf springassembly.

It has been proposed to employ rubber inserts between the spring leavesand to connect the springs to the body through rubber. This tends toreduce the shock of lateral displacement of the body incident to unequalflexure of the springs, the shock being somewhat cushioned, butincreases the-tendency of this lateral displacement to persist, the bodytending to move to and fro at a frequency which is determined by themass of the body and the lateral flexibility of the springs, the dampingaction normally resulting from interleaf friction having been largelyremoved by the use of the rubber inserts between the leaves.

It has also been heretofore proposed, in vehicles which employ rubber orother friction reducing inserts between the leaves of the vehiclesupporting springs, to anchor the body to the frame for the purpose ofpreventing the lateral body movement or float of the axle, but the meansemployed has usually consisted of a link or tie rod extending generallyparallel to the axle and pivoted at its ends to the axle and theiframe.l As either wheel rises, any point on the axle tendsto swingupwardly through an arc of which the center is located at the point ofcontact of the other wheel with the ground. Consequently, the arcdescribed by that end of the link or tie rod which is intended forconnection to the axle does not coincide with` the arc described by thatpoint on the axle selected for such connection. There is accordinglysome relative lateral displacement of the body and axle when such linksare employed,

which lateral displacement is undesirable.

It is therefore an object of the invention to provide a constructionwhich is reasonably effective in eliminating lateral movement of thebody i on the axle under the conditions stated and which will at thesame time guide the axle and body in the relative paths which theynormally tend to follow. More specifically, it is an object of theinvention to provide, in a wheel suspension offering low damping tolateral bodily oscillation, a connection between the body and the framein which the connecting means, it free from the axle, would describe anarc coinciding substantially with the arc described by that portion ofthe axle to which the connection is made. It is a feature of theinvention that the connecting means is pivoted to the frame and to theaxle at relatively low points so as to reduce to a minimum the lateraldisplacement of the body on the axle resulting from the use of suchconnecting means.

Again, if the damping of the springs is decreased in a vehicle employingthe well-known Hotchkiss type of drive, in which rotation oi' the rearaxle housing about a transverse axis is resisted largely .by thesprings, axle rotation in response to braking or driving torque becomesmore pronounced, with accompanying brake or clutch chatter. It is alsofound with springs of low damping characteristics that in driving oversand or snow, the wheels crawl upwardly on the soft surface, and as thevehicle weight breaks down this surface, the axle drops; this up anddown motion rotates the axle, setting up vibrational disturbances in theclutch and brakes. Such chatter also results from the employment ofl lowdamped springswhen the vehicle wheels bounce in passing over certaintypes of uneven road surface. The instant invention contemplates theconnection of the axle to the frame in such manner as to resist rotationof the axle and undesired flexing of the springs under suchcircumstances and consequently to eliminate this type of vibration.

Further objects and features of the invention will be apparent from thefollowing description taken in connection with the accompanyingdrawings, in which Figure 1 is a plan view of the rear end of. a

2 -i ,l motor vehicle illustrating the application oi' the -instantinvention thereto;

Figure 2 is a side elevation ofthe structure shown in Figure 1:

Figure Sis a sectional view taken substantially on the line 2 3 ofFlgure'l:

Figure 4 is a lcctionon the line 4--5 of Figure 1;

Figure 5 is ure 4;

' Figure 6 is alsection on the line 5-5 of Figure 2 Figure 7 is a-section on the line 1 1 of Figure 2; and

Figure 8 is .a section on the line H of. Figure 1. L

For convenience in describing the invention reference is madehereinafter to the form thereof illustrated in the drawings and specificlanguage is employed. It will nevertheless be understood that nolimitation of the scope ofthe invention is thereby intended. variousalterations and modifications being contemplated such as would normallyoccur tov one skilled in the art to which the invention relates.

Referring first to Figure 1 of the drawings, will be observed that themotor vehicle body is represented by the supporting side sills it, whichsills are connected by an x-frame structure of which the members Il areshown and by a cross frame member I2 at the extreme rear of the body.Road wheels I5 are supported on axle housings I5, which are in turnmounted on a 24. Intermediate the individual leaves of these springsrubber inserts 25 are provided. For example, as sh'ownmore particularlyin Figure 8,

Y the outer end of each leaf may be formed with a depressed portion orpocket 28 in which is re`- celved one of the inserts 25, the latterbearing Von. the next adjacent leaf and being of suiilcient thickness toseparate the spring leaves for a distance of several inches adjacent theend oi' the shorter leaf of each contiguous pair of leaves. 'I'helongest-leaf of each spring assembly is deformed at its forward end toprovide an eye 2l which embraces a rubber bushing 29,

as shown more particularly in Figure 7 of the drawings. The bushing 28in turn is received on a spindle 3l which is supported in a Ui-shapedbracket 3l, the latterbeing rigidly secured to the adjacent side silll0. At its rear end each spring assembly 24I is deformed to provide` anY eye portion I5 embracing a bushing 36 of rubber or the like, thelatter surrounding a spindle v38 which is pivotally mounted in theopposite sides I9 of a spring shackle. A second spindle Il is likewisepivotally supported in th'e shackle sides 39 and a bushing 43 of rubberor the like surrounds the spindle 4I. Surrounding the ed in a U-shapedyoke 45, the latter being rigidly a section on the line 5-5 of lilg--supported on the vehicle by means of leaf springs vbushing Il is acollar I4 which is in turn mountsecured to thel associated side sill I0at the rear thereof.

By reason of the employment of the Hotchkiss type of drive, in which thetorque tube for the drive sh'aft is eliminated and the drive shaft isbodily movement of the vehicle body on the axle` is offered.Consequently the construction is sub- `ject to chatter and the bodytends to vibrate or float laterally, as'hereinbefore pointed out, with'resultant discomfort to the passengers.

The details of the structure thus far described form no essential partof the instant invention, being merely illustrative of vehiclesuspension systems. of low damping, in which type of suspension systemmy invention is particularly useful. I therefore contemplate thepractice of my invention in connectionvwith various other types ofsuspension system in which the vsuspension springs or other elements ofthe system are so constructed or arrangedl as to permit or induce bodymovement or vibrational disturbances which can be overcome by theapplication of the principles of the invention. One method of applyingthese principles will now be explained with reference to theaccompanying drawings.

Secured to each. of the members il of the X-frame structure is adepending bracket 50. Supported at its opposite ends in the brackets 50is a bar 52 formed to provide'two angularly disposed arms, the nature ofthe supporting connection being shown more particularly in Figures 4 and5 of the drawings. Thus each of these connections may include agenerally rectangular casing 54 which is preferably completely filledwith a block or mass 53 of deformable material-such` as rubber. Each ofthe casings 54 is rigidly secured in any convenient manner to one of thebrackets 50, for example by bolting or riveting, and the opposite endsof the two arms of the bar 52 are flattened as at 55 and are bentinwardly to extend within the casings 54 and to seat within the rubber53 therein. The rubber connection just described affords adequateresistance to undesired movements of the body and axle. and serves notonly as a bearing requiring no lubrication, but also acts to cushionshocks which might be transmitted between the axle and the body if amore rigid type of connection were used.

Intermediate its ends the bar 52 is provided with a bearing portion 56,preferably of partispherical shape, which bearing portion is receivedwithin a complementary bearing bracket of which one part is formed in adepending boss 51 formed on the forward end and lower side or" thedierential housing and of which the other part is formed in a cap 58which is bolted or otherwise secured to the .boss 51, the constructionbeing such that the bar 52 may rotate freely with respect to thedifferential and axle housings.

It is found that as the road wheels rise and fall, the lower portion ofthe differential housing tends to move in an arc of generally circularshape, the location 4and radius of this arc being determined by thepoints of connection of the -and by the points oi' ilexure of thesesprings.

'I'his arc lies in a vertical longitudinal plane disposed mid-waybetween the road wheels. Conseque'ntly,4 it is possible to consider thisarc as defining the common base of two cones oi' which the apexes arelocated adjacent the side sills l0. In accordance with the presentinvention, the points of connection of the arms of the bar 4I2 to theframe are disposed at'the apexes of these cones. Thus the bearingportion 58 of the bar 52 would, if free, describe an arc coincidingsubstantially with the arc which ywould be described by thecomplementary bearing formed in the boss 51 of the differential housing,and the normal movement of the differential housing will therefore notbe impeded by reason of connection thereof to the frame through the bar52. It will be apparent, however, that any substantial lateral movementof the body on the axle will be resisted by the bar 52. Similarly anytendency of the axle and din'erential housings to rotate about atransverse axis will be resisted by this bar and the soft ride which isinherent in a suspension characterized by low damping is realizedwithout the disadvantages of axle vibration and body float hereinbeforedescribed.

While the invention has been described with reference to the suspensionfor the rear end of the vehicle, in which relationship it is mostuseful, it will be apparent that certain features and advantages of theinvention can be attained by applying the same to the suspension at theforward end of the vehicle.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. In a motor vehicle, the combination with a vehicle frame, road wheelsdisposed at opposite sides of said frame, axle means carrying said roadwheels, resilient means supporting said axle means and road wheels onsaid frame for rising and falling movement and for limited lateralmovement with respect thereto, said means yieldably constraining saidaxle to rising and falling movement in a path such that a point on saidaxle describes a generally circular arc in a vertical longitudinalplane, said means comprising longitudinal leal spring means having oneend thereof connected to said frame against longitudinal displacement,and means acting between said axle Ymeans and said frame for resistingrelative lateral movement thereof, said last named means including amember having articulated connection with said axle, means at said pointand with said frame at a point located substantially at the apex of acone of which the said arc defines the base.

2. In a motor vehicle, the .combination with a vehicle frame, roadwheels disposed at opposite sides of said frame, axle means carryingsaid road wheels, resilient means supporting said axle means and roadwheels on said frame for rising and falling movement and for limitedlateral movement with respect thereto, said means yieldably constrainingsaid axle to rising and falling movement in a path such that a point onsaid axle describes a generally circular arc in a vertical longitudinalplane, said means comprising longitudinal leaf spring means having oneend thereof connected to said frame against longitudinal displacement,and means acting betwen said axle means and said frame for resistingrelative lateral movement thereof, said last namedmeans including amember having articulated connection with said axle means at said pointand with said frame at points on, opposite sides of the vehicle, whichlast named points are located substantially at the apexes means adjacentthe mid-point of the length of the latter for resisting lateral movementof said frame on said axle means, said last named means including amember having arms directed laterally and extending forwardly from saidaxle means.

4,. In a motor vehicle, the combination with a vehicle frame, of roadwheels associated with said frame, axle means carrying said road wheels,means yieldingly supporting said road wheels and axle means on saidframe for rising and falling movement with respect thereto, and rigidmeans having articulated connection with said axle means and pivotallyconnected to said frame for resisting rotation of said axle means abouta transverse axis, said last named means including a member transverselypivoted to said axle means beneath the axis of the latter and extendingforwardly and laterally for pivotal connection to said frame.

5. In a, motor vehicle, the combination with a vehicle frame, of roadwheels associated with said frame, axle means carrying said road wheels,means yieldingly supporting said road wheels and axle means on saidframe for rising and falling movement with respect thereto, and meanshaving articulated connection with said frame and with said axle meansfor resisting rotation of said axle'means about a transverse axis, saidlast named means including a member extending longitudinally andlaterally from said axle means, the point of articulated connectionbetween said member and said axle means being below the transverse axisof said axle means and affording relative movement therebetween about atransverse axis.

6. In a motor vehicle, the combination with a vehicle frame, of roadwheels associated with said frame, axle means carrying said road Wheels,means yieldingly supporting said road wheels and axle means on saidframe for rising and falling movement with respect thereto, and meanshaving articulated connection with said frame and with said axle meansfor controlling the relative movements ofthe latter, said last namedmeans comprising a rigid member, generally V-shaped in plan, havingtheapex thereof transversely pivoted to said axle means adiacent Y saidaxle means for controlling the 'relativemovements oi.' the latter. saidlast named means oomprising a rigid member, generally V-shaped in plan,having the apex thereof transversely pivoted to said axle means adiaeentthe mid-point of the length of the latter and the extremities thereofpivoted to the frame at opposite sides of the ,latter and forwardly ofsaid axle means. andv rubber interposed insaidlastnamedmeans be tweensaid axle means and said frame.

8. In a motor vehicle, the combination with a vehicle frame, of roadwheels associated with said frame, axle means carrying said road wheek,means yieldingly supporting said road wheels and axle means on saidframe for rising and falling movement with respect thereto, and meanshaving articulated connection with said frame and ciated with saidframe, axle and dierential housing means carrying said wheels, resilientmeans supporting said road wheels and housing means on said frame forrising and falling movement and ior limited lateral movement withrespect thereto. and a generally v-shaped bar having the apex thereofpivoted to the lower portion of said diiferential housing means and thearms thereof diverging forwardly and pivotally connected to oppositesides of said frame.

10. In a motor vehicle, the combination with a vehicle frame, reardriving road wheels associated with said frame. axle and diilerentialhousing means carryingv said wheels, resilient means supporting saidroad wheels and housing means on said frame for rising and fallingmovement and for limited lateral movement with respect thereto, agenerally V-shaped bar having the 'apex thereof pivoted to the lowerportion of said differential housing means and the arms thereofdiverging forwardly and pivotally connected to opposite sides of saidframe, and means including "rubber interposed between said bar and saidframe.

' FRANK C. BEST.

